Grading Policy

The material on this page is organized as follows:

  1. Final Grades
  2. Letter Grades
  3. Homework Problem Types
  4. Extra Credit
  5. Cheating
  6. Discussion, Cooperation, and Collaboration

Final Grades

You will receive one grade for each homework and test (including the final exam). An estimate of your final grade will be made by taking a weighted average of these grades, with the total weight on homeworks being the same as the total weight of the tests. Each exam is weighted equally with the others; no extra weight is given to the final exam. Each homework point counts equally, but some homeworks have more points than others. We will then take extra credit and other factors into consideration to make small adjustments.

We reserve the right to adjust your calculated grade downward (towards F) if you do not turn in the homework problems, but get good grades on the tests.

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Letter Grades

Your grade is independent of anyone else's grade in this class. That is, we do not grade on a curve, and everyone can get an A. Our purpose in grading is to uphold a standard of quality and to give you feedback: it is not to rank students.

Instead of using curve grading as a final defense against problems that are too hard, we use the following policy. If a problem on a homework or exam is so hard that most students do not "get it", then we will eliminate it from the exam or homework grading. If this problem was appropriate, then we will teach how to solve problems like it, and give a similar problem on another exam or homework. If it was not appropriate, then we will ignore it. If you detect such a problem on a homework, let us know about it as soon as possible, as it will save us all a lot of work.

The grading in this class will include subjective components. For example, the grading of proofs is (perhaps surprisingly) subjective. In grading proofs we will emphasize clarity. In grading essay answers, we will weight both the force of your arguments and how completely they consider all the issues.

Although we will not always make fine distinctions in points the nominal minimum standards are given by the following table.


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Homework Problem Types

There are 3 kinds of homework problems: normal, suggested practice, and extra credit. Normal problems are essential material. If you find yourself struggling with one more than a reasonable amount of time, please come and see us for help! Suggested practice problems are for you to use for practice, if you wish, but not to hand in; suggested practice problems may be discussed in discussion sections, and make good study problems for tests. Extra credit problems do not count as normal problems, but can be handed in. They are discussed further below.

On homeworks, the points and type of problem follow the problem number. For example, "3. (25 points)" is a normal problem, while "4. (suggested practice)" is a suggested practice problem, and "5. (20 points; extra credit)" is an extra credit problem.

The points used to figure your grade on a homework are the points you earn for the normal problems.

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Extra Credit

You may accumulate extra credit points on problems marked extra credit. Extra credit problems should be turned in within one week of the due date of the last normal problem of the homework to which they are attached. However, all extra credit work must be handed in before the last week of classes.

Extra credit problems should be turned in separately from regular homework problems. That is, don't staple them together with regular homework problems. Make sure they are also labeled with your name and clearly state what problems are being solved.

The main reason to do extra credit work should be that you are interested in the problems and want to learn more about the material. Since the main material is more important, you should only do extra credit problems that interest you and that you have time for. Beware that one reason for having extra credit problems is to give me a place to put interesting problems that are of unknown difficulty. Sometimes these turn out to be quite hard.

Another reason, for doing extra credit work, however, is that your extra credit points will be used to subjectively raise your final grade in the class. For example, if you are close to an A in the class, and have some extra credit points, then we will take them into account and may raise your grade to an A. Another use for extra credit points is to impress me, if you want me to write you a recommendation someday. (Because of that, it is wise to save your extra credit work.) However, you can't use extra credit work to make up for incomplete work. If you are having difficulty in the class, focus on the main material, not on the extra credit work.

You may also do work for extra credit that you invent, but please check with me before doing something like that. (Otherwise you may spend a lot of time on something that I may not consider worth many extra credit points.)

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The simple rule of thumb is:

Never give or use someone else's code or written answers.

Such exchanges are definitely cheating and not cooperation.

We will take action if we catch you cheating on a test or exchanging code or written answers. Read the section on academic dishonesty in the Iowa State University Catalog.

If you honestly believe that certain problems are too much busy work, then bring it to the instructor's attention; or failing that, only do the part of the problem that you think you need to do to learn the material and explain that to us.

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You are encouraged to discuss homework, and other parts of the class with other students. Such discussions about ideas are not cheating, whereas the exchange of finished, written answers is cheating. However, when you have more than casual discussions about homework problems, you must cite the other person as described below.

When you cooperate on solution ideas or collaborate on producing final answers, you must cite the other people you worked with as follows. This must be done for each problem on which you cooperate or collaborate. (That is, if you work with someone on a problem, you don't need to work with them on the entire homework.)

Note that substantial collaboration on solutions which is not cited as described above is considered cheating. In particular, if you are part of a group that divides up the problems in a homework, and some do each one, without actively contributing during the solution of each problem, then this is just an exchange of finished answers--i.e., cheating. Such cheating will be dealt with as described above. It should be clear that you will learn less by such exchanges of finished answers.

Be careful, not to get involved in an unequal collaboration, where you are doing less work than someone else. Part of what you need to do to learn the material is to struggle with it; if you deny yourself that struggle, you will learn less and remember what you learned less. So beware of this trap.

Also, as a kindness to your classmates, you should terminate an unequal collaboration where you are doing more than the other person. The other person will learn the material better if you help them but don't collaborate so closely. In this case it's better to help them only by discussing problems with them, and not by jointly collaborating on solutions.

Finally, if you use reference materials (other than the course texts) to solve a problem, you must give a citation. This includes material from the web. Not doing so is plagiarism (i.e., cheating). We take plagiarism quite seriously, so note this policy well.

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Last modified Sunday, January 8, 2006.

This web page is for the Spring 2006 offering of Com S 641 at Iowa State University. The details of this course are subject to change as experience dictates. You will be informed of any changes. Thanks to Curtis Clifton for help with these web pages. Please direct any comments or questions to Gary T. Leavens.